Process for producing woollike effects on cotton fabrics



, ed sulphuric acid, a permanent structural Patented Feb. 8, 1927.

UNITED STATES 1,616,749 PATENT OFFICE.

HAROLD I. HUEY, 'OF SAYLESVILLE, RHODE ISLAND, ASSIGNOR TO SAYLES FINISHING PLANTS, INC., OF SAYLESVILLE, RHODE ISLAND, A CORPORATION OF RHODE v ISLAND.

PROCESS FOR PRODUCING WOOLLIKE EFFECTS ON COTTON FABRICS.

No Drawing. Application filed May 5, 1922, Serial No. 558,763. Renewed September 30, 19'24.

This invention relates to processes for treating unmercerized cotton fabrics for the production of a wool-like finish.

It is now well known that if a cotton fabric be subjected to the action of concentratchange, takes place in the fibres which remains even though the treated fabric be washed. In 18 1 1 Mercer suggested that a cotton fabric will assume a parchment-like quality provided the sulphuric acid be of a concentration between 495 and 535 Baum, and since that time Blondell and others have. found that the change in the cellular structure of cotton goods varies as the concentration of the sulphuric acid is raised or lowered. Other factors further influence the effects produced on cotton fabrics by the acid treatment, such, for instance, as the character or condition of the fabric at the time of the acid treatment, the

temperature and length of time the acid,

' treatment continues. i

It has been observed, heretofore, that the action of sulphuric acid of a concentration of less than 51 B., is much more intensive and imparts to cotton fabrics new properties or characteristics if the cotton has been previously mercerized and thereby rendered more susceptible to the action of the acid,

and that the mercerizing luster disappears while the fabric assumes a fine, light, or wool-"like nature. Repeated treatments of the mercerized fabric by sulphuric acid of 49 to 50 B. concentration and alkali lye have been heretofore suggested as increasing the wool-like effects produced, provided that a treatment with one of the re-- vation that an unmercerized cotton fabric treated with sulphuric acid of a. concentration of from 51 to 53 B. at a temperature of'about 15 0., and then with caustic soda of about one-half the strength usually employed in a mercerizing, or from 15 to 22 not continue more than about two minutes,

and preferably less, while thecaustic soda treatment at the concentration indicated may continue from twenty to thirty minutes or more.

In accordance with the present invention, the cotton fabric which has not been previously mercerized is freed from the sizing, finlshin agents, natural gums, and waxes by boihng, and the fabrics may be then bleached and dried.

The unmercerized fabric is then treated with sulphuric acid of a concentration between 51 and 53 B. at a temperature between 14" and 16 C. This treatment has a swelling action on the fabric and fulls and shrinks'it. The length of time during which the action of the acid continues may vary, but preferably is less than two minutes, which is found to be sufficient to produce the desired effect."

The treated fabric is now washed and dried, after which it is subjected to the action of caustic soda at a concentration of about one-half the strength usually em-- ployed in the mercerization process or of a concentration of from 15 to 22 B. at a temperature of between 30 and 35 C. The strength of the caustic soda is such that it not previously treated, and under the conditions and in accordance with the present invention it serves to impart to the fabric the desired Sheerness, firmness, and finished wool-like appearance.

The treatment with the caustic soda at the concentration described may continue for would have no mercerizing effect on fabrics R v of caustic soda of concentration of from 15 to 22 B. at a temperature between 30 and 35 C. and washing the treated fabric.

2. The process described for imparting to unmercerized, cotton fabrics a wool-like appearance, consisting in causing concentrated sulphuric acid of from 51 to 53 B. to act upon the unmercerized fabric at a temperature of from 14 to 16 C. then washing and drying the fabric, subjecting the fabric to the action of caustic soda of a concentration between 15 and 22 B., and washing the treated fabric. i 3. The process described for imparting a wool-like appearance to unmercerized cotton fabrics. consisting in boiling the unmercerized fabric and drying it, then causing sulphuric acid of concentration from 51 to 53 B6. to act'upon the fabric for not more than two minutes, then washing and drying the action of caustic so a of a concentration of between 15 to 22 B. at a temperature above 30. 0., and then washing the fabric.

4. The process described for impartingl to unmercerized cotton fabrics a wool- 'ke character, both as to feel and appearance, consisting in first eliminating the natural gums, waxes, and finishing agents from the unmercerized fabric, then bleaching the fabric, then causing sulphuric, acid of concentration between 51 and 53 B. to act upon the fabric at a temperature of from 14 to,

16 0., washing and drying the fabric, then subjecting the fabric to the action of caustic soda of from 15 to 22 B., and then washing the fabric.

In testimony whereof, I have signed my name to this specification.

HAROLD I. HUEY. 

